Sediment-Water Column Exchanges of Nutrients and Oxygen in the Tidal James and Appomattox Rivers

摘要

Fluxes between the sediments and overlying water of ammonium, nitrate, total phosphorus, ortho phosphorus, and dissolved oxygen have been measured in the tidal James and Appomattox Rivers, VA. A total of 68 nutrient flux measures, 203 oxygen flux measures, and 18 control measures were collected in the summer months, 1983 and 1984. Ammonium is predominantly released from the sediments at a mean rate of 9.82 mg/sq m/hr. Nitrate is predominantly taken up by the sediments at a mean rate of 1.53 mg/sq m/hr. Total phosphorus is taken up by the sediments at a mean rate of 1.67 mg/sq m/hr. Ortho phosphorus may be taken up or released. Mean flux is an uptake of 0.75 mg/sq m/hr. Dissolved oxygen is taken up at a mean rate of 44 mg/sq m/hr.